1. Field of the Invention
The present invention relates generally to X-ray tubes and, more specifically, to a driver for powering an X-ray tube able to provide constant and adjustable power to the X-ray tube without significant thermal buildup from the creation of X-rays.
2. Description of the Prior Art
Numerous types of power supplies have been provided in the prior art. For example, U.S. Pat. Nos. 3,195,038; 3,711,747; 3,938,031 and 5,589,760 all are illustrative of such prior art. While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described.
This invention relates to a voltage or current regulator apparatus, e.g. variable ratio transforming apparatus for the conversion of electrical energy from one voltage or current to another. The invention includes a plurality of transformer windings or sources of alternating current, a plurality of switch means associated with the windings. Each switch is changeable between a condition in which it connects the associated winding or source into a circuit and a condition in which the associated winding is by-passed in the circuit without being short circuited. A control device causes the switches to connect one or more of the windings in series.
A power supply for use with different AC line voltages, which includes a power transformer having a plurality of separate primary windings and a corresponding plurality of fuses connected thereto. The primary windings are connected to each other in several different ways to change the turns ratio of the power transformer depending upon the value of the voltage supplied thereto. Thus, a predetermined voltage is produced in the secondary winding of the transformer irrespective of the value of the supplied AC line voltage and the current flowing through each of the fuses is held substantially constant, during normal operating conditions, regardless of the manner in which the separate primary windings are connected.
An adjustable voltage alternating current power supply is provided which is especially suitable for supplying loads of variable resistance. The power supply consists of a transformer having two secondary windings with solid-state switches for alternatively connecting the secondary windings in either parallel or series, and with a firing control circuit for changing the connection of the windings from parallel to series at a predetermined point in each half-cycle of the voltage to adjust the effective output voltage so that constant output power can be maintained, or the output power can be varied in any desired manner.
A voltage converter for traveler""s uses includes: a 50 watt (0-50 W) transformer for converting an input voltage of 220 VAC to an output voltage of 110 VAC for normally powering a load of 50 watts or less; a 1600 watts (50-1600 W) transformer for converting an input voltage of 220 VAC to and output voltage of 110 VAC for powering a load ranging from 50 watts to 1600 watt; and a sensing control circuit operatively sensing an output load having a power rating larger than 50 watts (50 W to 1600 W) for operatively actuating a relay for automatically switching an output terminal of the 50 watts transformer to the output terminal of the 1600 watts transformer for preventing burning or damaging of the output load connected with the voltage converter and for protecting the voltage converter itself.
The present invention relates generally to X-ray tubes and, more specifically, to a driver for powering an X-ray tube able to provide constant and adjustable power to the X-ray tube without significant thermal buildup from the creation of X-rays.
A primary object of the present invention is to provide a X-ray tube driver that will overcome the shortcomings of prior art devices.
Another object of the present invention is to provide a X-ray tube driver which is able to drive an X-ray tube directly using a high voltage transformer.
A further object of the present invention is to provide a X-ray tube driver which is able to provide the constant pulse to the X-ray tube without significant thermal buildup from the creation of X-rays.
A yet further object of the present invention is to provide a X-ray tube driver which is able to provide an adjustable pulse of 0-40 kV or 0-80 kV to an X-ray tube but not limited by these boundaries.
A still further object of the present invention is to provide a X-ray tube driver which is small and light weight.
An even further object of the present invention is to provide a X-ray tube driver which is able to vary the frequency of pulses to thereby change the number of X-rays generated per second.
A still further object of the present invention is to provide a X-ray tube driver which is able to vary the voltage of pulses thereby changing the amount of X-ray penetration through a desired object being X-rayed.
A yet further object of the present invention is to provide a X-ray tube driver which is able to vary output pulses over a set time to get the best possible image of the object being X-rayed.
Another object of the present invention is to provide a X-ray tube driver wherein there is no significant heat build up in the X-ray tube due to X-ray generation.
A still further object of the present invention is to provide a X-ray tube driver which is able to control the current, through the x-ray tube, of the voltage pulses thereby changing the amount of X-ray beam power through an object being X-rayed.
An even further object of the present invention is to provide a X-ray tube driver which is able to pulse an X-ray tube with at least 70 watt pulses without heat sinking the tube and preventing voltage tracking across the tube, but not limited to 70 watt pulses.
A further object of the present invention is to provide a X-ray tube driver that is simple and easy to use.
A still further object of the present invention is to provide a X-ray tube driver that is economical in cost to manufacture.
Additional objects of the present invention will appear as the description proceeds.
A driver circuit for supplying power to an X-ray tube including a filament supply, a first transformer connected to an anode of the X-ray tube and a first switch connected between the driver control and first transformer is disclosed by the present invention. The driver control controls the first switch to move between an open and closed position. The signal applied to the first transformer when the switch is closed is adjustable in both frequency and pulse width and is applied to the X-ray tube to generate an adjustable voltage and frequency for producing an X-ray beam. The first transformer includes a primary winding connected to the first switch and a secondary winding connected to an anode of the X-ray tube, a current to be induced in the secondary winding is applied to the anode of the X-ray tube for generating the X-ray beam. The X-ray tube driver may further include a second switch; a second transformer connected between the second switch and a cathode of the X-ray tube; and a third transformer connected in parallel with the filament of the X-ray tube, the second transformer being connected in series with the parallel connection of the third transformer connected to the cathode and ground potential. The second transformer applies a negative voltage to the cathode. The driver circuit is able to provide a high voltage pulse having a width within a range of 100-200 xcexcsec but not limited to that range. The high voltage pulse is able to generate a voltage within a range of 0-40 k and a range of 0-80 kV when the second and third transformers are connected, but not limited to those ranges.
To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.